STEAM VS. HOT WATER. 41 



The old method of heating by means of the large cast iron 

 pipes is not adapted to the forcing business. The com- 

 parative merits of steam and water as media for conveying 

 heat have been much discussed in recent years, with the 

 result that neither system has gained a complete victory. In 

 other words, each system has peculiar merits. Our own 

 experience emphasizes the greater value of steam, but we 

 do not condemn hot water. We believe that steam is 

 superior for very large houses where the fall is slight, for 



27. The laying of lapped glass. 



most forcing-houses, and for all establishments which are 

 likely to be often modified and extended. It is particularly 

 desirable in the forcing of such "warm" plants as tomatoes 

 and melons. For conservatory purposes, for straight runs 

 and small and cool houses, it is equaled probably sur- 

 passed in many instances by water. Steam overcomes 



